OFFSET
1,1
COMMENTS
Row 4 of A216338
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..19
EXAMPLE
Some solutions for n=4
..0..x..1..x....0..x..1..x....0..x..1..x....0..x..1..x....0..x..1..x
..x..2..x..3....x..2..x..3....x..2..x..3....x..0..x..1....x..2..x..3
..4..x..0..x....4..x..5..x....3..x..1..x....2..x..3..x....0..x..2..x
..x..5..x..3....x..3..x..0....x..3..x..1....x..2..x..1....x..0..x..4
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 04 2012
STATUS
approved